The present invention relates to a vehicle and a method for controlling thereof according to the description herein.
The vehicle can be of many different types, and the invention includes both driver controlled as well as driver-less, remote controlled vehicles. The invention is however in particular, but not exclusively, directed towards vehicles which will move in environments where space is relatively limited and where high demands are placed on the vehicles' manoeuvrability, as is the case for industrial trucks, which are driven in warehouses, industrial sites, loading yards and other such places to handle cargo. For this reason the invention will hereafter mainly be described in connection with vehicles of such so-called truck type without limiting the invention in any way thereto.
A vehicle of the type defined by way of introduction is known from the applicant's patent application PCT/SE99/00618. By arranging said two first wheels in the indicated way excellent properties to displace such a vehicle in a confined space according to advantageous movement patterns are achieved. The reason for this is that it can be said that such a wheel can be turned on the spot without any tendency to slip in that on turning the wheel one revolution around the first axis it will with said turning point describe a circle on the ground. At the same time it is made possible to take up new alignments of the wheel while the chassis is totally still, which means that the vehicle can be brought to a new position in the shortest possible or otherwise most desirable way.
It is stated here that the invention is fully realisable with only said first wheels of said first type and no other means resting on the ground to support the chassis, so that in this case the vehicle has to be balanced like a motorcycle, even if hereafter the diagrams and the accompanying text show and describe the case of a vehicle with four wheels, as this is the way the vehicle will usually be realised. The desire exists to improve the way in which the vehicle of the discussed type is controlled in order to make full use of the excellent possibilities of displacement patterns which such a vehicle offers.